Compare · ModelsLive · 2 picked · head to head
GPT-5 Chat vs Step 3.5 Flash
Side by side · benchmarks, pricing, and signals you can act on.
Winner summary
GPT-5 Chat wins on 1/1 benchmarks
GPT-5 Chat wins 1 of 1 shared benchmarks. Leads in arena.
Category leads
arena·GPT-5 Chat
Hype vs Reality
Attention vs performance
GPT-5 Chat
#1 by perf·#1 by attention
Step 3.5 Flash
#7 by perf·#11 by attention
Best value
Step 3.5 Flash
26.4x better value than GPT-5 Chat
GPT-5 Chat
14.6 pts/$
$5.63/M
Step 3.5 Flash
384.5 pts/$
$0.20/M
Vendor risk
Mixed exposure
One or more vendors flagged
OpenAI
$840.0B·Tier 1
StepFun
$5.0B·Tier 1
Head to head
1 benchmark · 2 models
GPT-5 ChatStep 3.5 Flash
Chatbot Arena Elo · Overall
GPT-5 Chat leads by +34.7
GPT-5 Chat
1426.0
Step 3.5 Flash
1391.4
Full benchmark table
| Benchmark | GPT-5 Chat | Step 3.5 Flash |
|---|---|---|
Chatbot Arena Elo · Overall | 1426.0 | 1391.4 |
Pricing · per 1M tokens · projected $/mo at 10M tokens
| Model | Input | Output | Context | Projected $/mo |
|---|---|---|---|---|
| GPT-5 Chat | $1.25 | $10.00 | 128K tokens (~64 books) | $34.38 |
| Step 3.5 Flash | $0.10 | $0.30 | 262K tokens (~131 books) | $1.50 |